Revert of MemoryCache: make sure that Resources are evicted only when they can be deleted (https://codereview.chromium.org/179943002/)

Reason for revert:
Possibly causing crashes in MultiProfileFileManagerBrowserTest

See: http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_chromeos_rel/builds/7766

Original issue's description:
> MemoryCache: make sure that Resources are evicted only when they can be deleted
> 
> This CL fixes a problem where Resources can be taken out of the cache but not
> deleted (if their handle count is not 0 for example).
> 
> BUG=290193
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=170311

TBR=pliard@chromium.org,japhet@chromium.org,eustas@chromium.org,clamy@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=290193

Review URL: https://codereview.chromium.org/217643003

git-svn-id: svn://svn.chromium.org/blink/trunk@170380 bbb929c8-8fbe-4397-9dbb-9b2b20218538